1. Field of Invention
This invention generally relates to systems and methods for detecting impending faults within closed-loop control systems.
2. Description of Related Art
To achieve consistent operational quality, complex electromechanical systems generally use closed-loop process controls. In an exemplary closed-loop control system, an actuator influences the operation of a component so that the amplitude of an error signal, generated in response to deviations by the actuator from a defined normal condition, is minimized.
Operational quality is defined by the operating space of the system. An operating space is the range of sensor readings around a target value in which nominal operating conditions are maintained.
Changes in the process dynamics, such as environmental changes or aging of the components, may warrant changes in the targets for maintaining the same consistent performance. As a result, the operating space also changes. The process is under control only so long as the targets and the actuators are within the operating space defined by the respective allowable range of variation around their nominal values. This process continues until the system cannot operate within the operating space and a fault is declared.